Patent application title: METHOD AND TERMINAL FOR PROVIDING A ROUTE IN A NAVIGATION SYSTEM USING SATELLITE IMAGE

Abstract:

A method and a terminal for providing a route in a navigation system using
a satellite image are provided. The terminal includes a route calculation
unit for calculating a route from a current location to a destination
when a user inputs the destination, a satellite image requesting unit for
requesting a satellite image server for satellite images corresponding to
locations on the route and for downloading the requested satellite
images, a satellite image storage unit for storing the downloaded
satellite images, and a controller for retrieving a satellite image
corresponding to the current location from the satellite image storage
unit and for displaying the retrieved satellite image simultaneously
while downloading the satellite images corresponding to the locations on
the route.

Claims:

1. A terminal for providing a route in a navigation system using a
satellite image, the terminal comprising:a route calculation unit for
calculating the route from a current location to a destination when a
user inputs the destination;a satellite image requesting unit for
requesting a satellite image server for satellite images corresponding to
locations on the route and for downloading the requested satellite
images;a satellite image storage unit for storing the downloaded
satellite images; anda controller for retrieving a satellite image
corresponding to the current location from the satellite image storage
unit and for displaying the retrieved satellite image simultaneously
while downloading the satellite images corresponding to the locations on
the route.

2. The terminal as claimed in claim 1, wherein the controller displays the
satellite image together with a digital map for the navigation by means
of a split screen.

3. The terminal as claimed in claim 1, wherein the controller displays the
retrieved satellite image and zooms in/out according to a user input.

4. The terminal as claimed in claim 1, wherein the satellite image
requesting unit first downloads a satellite image corresponding to the
current location and then downloads satellite images corresponding to
next locations on the route.

5. The terminal as claimed in claim 4, wherein while the satellite image
requesting unit downloads satellite images and the satellite image
storage unit stores the satellite images, the controller retrieves and
displays an already stored satellite image corresponding to the current
location.

6. A method for providing a route in a navigation system using a satellite
image, the method comprising:calculating a route from a current location
to a destination when a user inputs the destination;requesting a
satellite image server for satellite images corresponding to locations on
the route;downloading the satellite images;storing the downloaded
satellite images;retrieving a satellite image corresponding to the
current location from a satellite image storage unit; anddisplaying the
retrieved satellite image while simultaneously downloading the satellite
images corresponding to the locations on the route.

7. The method as claimed in claim 6, further comprising displaying the
retrieved satellite image together with a digital map for navigation by
means of a split screen.

8. The method as claimed in claim 6, wherein the displaying of the
retrieved satellite image comprises displaying the retrieved satellite
image and zooming in/out according to a user input.

9. The method as claimed in claim 6, wherein the downloading of the
satellite images comprises:downloading a satellite image corresponding to
the current location; andcontinuing to download satellite images
corresponding to next locations on the route.

10. The method as claimed in claim 9, wherein while the satellite images
are downloaded, an already stored satellite image corresponding to the
current location is retrieved and displayed for navigation.

Description:

PRIORITY

[0001]This application claims the benefit under 35 U.S.C. §119(a) of
a Korean patent application filed in the Korean Industrial Property
Office on Mar. 06, 2007 and assigned Serial No. 2007-22117, the entire
disclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

[0002]1. Field of the Invention

[0003]The present invention relates to a method and a terminal for
providing a route in a navigation system. More particularly, the present
invention relates to a method and terminal for providing a route in a
navigation system using a satellite image.

[0004]2. Description of the Related Art

[0005]A car navigation terminal informs the driver of current location
information and provides an optimal route from a current location to a
desired destination. The terminal also guides the driver according to the
optimal route and provides the driver with a variety of information
beneficial for driving. One method for effectively providing information
about a route includes the displaying of a digital map and informing of a
current location on the road using the map.

[0006]Meanwhile, an Internet portal server, such as Google, Yahoo and the
like, has actively provided a map service based on satellite images. Use
of such satellite images enables checking of surroundings or roads, which
are not displayed on a conventional two-dimensional map.

[0007]As a result, navigation guidance has recently been enhanced with a
sense of reality by using these satellite images, which are received from
a satellite and are substantially the same as real pictures.

[0008]However, in order to display a satellite image on a screen, a
navigation terminal must download a satellite image corresponding to a
current location from a server via a communication network. In this case,
a period of time is required to download a satellite image from the
server. Therefore, when a car moves at a high speed, it is difficult to
display a satellite image corresponding to a current location on a screen
in real time. Even in a case in which the car moves at a low speed, if a
period of time is not enough to download a satellite image, it is not
possible to display a satellite image in real time and it is difficult to
provide a user with accurate guidance information.

[0009]That is, a navigation terminal requests a server for a satellite
image corresponding to the current location of the navigation terminal in
order to receive satellite information. Then, when the current location
of the navigation terminal changes, the navigation terminal again
requests the server for a satellite image for the changed location.
Therefore, it is difficult to display the satellite image in real time.

[0010]Therefore, a need exists for a navigation terminal and method for
providing a navigation route capable of displaying a satellite image
corresponding to a current location in real time.

SUMMARY OF THE INVENTION

[0011]An aspect of the present invention is to address at least the
above-mentioned problems and/or disadvantages and to provide at least the
advantages described below. Accordingly, an aspect of the present
invention is to provide a method and a terminal for providing a route in
a navigation system, which can acquire a satellite image corresponding to
a current location and can display the acquired satellite image in real
time.

[0012]Another aspect of the present invention is to provide a terminal for
downloading necessary satellite images from a satellite image server
based on route information, and providing route guidance to a user in
real time.

[0013]In accordance with an aspect of the present invention, a method for
providing a navigation route by using satellite images is provided. The
method includes, when a user sets a destination, calculating a route from
a current location to a destination, requesting a satellite image server
for satellite images corresponding to locations on the route, downloading
satellite images corresponding to the route, storing the downloaded
satellite images, retrieving a satellite image corresponding to the
current location from a satellite image storage unit and displaying the
retrieved satellite image simultaneously while downloading the satellite
images corresponding to the locations on the route.

[0014]In accordance with another aspect of the present invention, a
navigation terminal is provided. The terminal includes a route
calculation unit for calculating a route from a current location to a
destination when a user inputs the destination, a satellite image
requesting unit for requesting a satellite image server for satellite
images corresponding to locations on the route and for downloading the
requested satellite images, a satellite image storage unit for storing
the downloaded satellite images, and a controller for retrieving a
satellite image corresponding to the current location from the satellite
image storage unit and for displaying the retrieved satellite image
simultaneously while downloading the satellite images corresponding to
the locations on the route.

[0015]Other aspects, advantages, and salient features of the invention
will become apparent to those skilled in the art from the following
detailed description, which, taken in conjunction with the annexed
drawings, discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]The above and other aspects, features and advantages of certain
exemplary embodiments of the present invention will be more apparent from
the following detailed description taken in conjunction with the
accompanying drawings, in which:

[0017]FIG. 1 illustrates a navigation system according to an exemplary
embodiment of the present invention;

[0018]FIG. 2 is a block diagram illustrating a construction of a
navigation terminal according to an exemplary embodiment of the present
invention;

[0019]FIG. 3 illustrates a data structure of satellite images stored in a
satellite image server according to an exemplary embodiment of the
present invention;

[0020]FIG. 4 illustrates image blocks corresponding to locations on a
navigation route according to exemplary embodiment of the present
invention; and

[0021]FIG. 5 is a flow diagram illustrating a process of controlling
navigation route guidance by a navigation terminal according to an
exemplary embodiment of the present invention.

[0022]Throughout the drawings, like reference numerals will be understood
to refer to like parts, components and structures.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0023]The following description with reference to the accompanying
drawings is provided to assist in a comprehensive understanding of
exemplary embodiment of the present invention as defined by the claims
and their equivalents. It includes various specific details to assist in
that understanding but these are to be regarded as merely exemplary.
Accordingly, those of ordinary skill in the art will recognize that
various changes and modifications of the embodiments described herein can
be made without departing from the scope and spirit of the invention.
Also, descriptions of well-known functions and configurations will be
omitted for clarity and conciseness.

[0024]FIG. 1 illustrates a navigation system according to an exemplary
embodiment of the present invention.

[0025]Referring to FIG. 1, a navigation terminal 100 connects to the
Internet (not shown) through a wireless data communication network 200
such as a wireless Local Area Network (LAN), Wide-band Code Division
Multiple Access (WCDMA) and the like, thereby establishing a connection
with a satellite image server 300. The data communication network 200 can
support the Internet. After connecting to the satellite image server 300,
the navigation terminal 100 can download necessary satellite image data
from the satellite image server 300 and display the downloaded data for
navigation.

[0026]FIG. 2 is a block diagram illustrating a construction of a
navigation terminal according to an exemplary embodiment of the present
invention. Referring to FIG. 2, the navigation terminal includes a
controller 110, a wireless unit 102, a key input unit 104, and a display
unit 106. The controller 110 controls overall operations of the
navigation terminal. The wireless unit 102 converts voice data and
control data into wireless signals and transmits the converted signals to
the data communication network 200. The wireless unit 102 receives
wireless signals, for example from the data communication network 200,
converts the received wireless signals into voice data and control data,
and outputs the converted signals to the controller 110. Therefore, the
wireless unit 102 can communicate with the satellite image server 300
through the wireless data communication network 200 such as wireless LAN,
WCDMA and the like.

[0027]A key input unit 104 may include a plurality of number keys and
character keys, and outputs input signals generated by a user's key
pressing to the controller 110. A user may input a destination through
the key input unit 104 or select a destination displayed on the display
unit 106.

[0028]The display unit 106 may include a display device such as a Liquid
Crystal Display (LCD), and displays navigation screens corresponding to
the user input. The display unit 106 may also include a touch screen so
as to function as a display and as an input device.

[0029]Further, the navigation terminal 100 includes a route calculation
unit 112, a satellite image requesting unit 114, and a satellite image
storage unit 116. When a user inputs a destination through the key input
unit 104, the route calculation unit 112 calculates a route from a
current location to the destination. The calculated route information is
provided to the controller 110 for providing a navigation service to a
user. Also, the calculated route information is provided to the satellite
image requesting unit 114. The satellite image requesting unit 114
requests, through the wireless unit 102, the satellite image server 300
for satellite images corresponding to locations on a route from a
starting point to a destination point based on the calculated route
information. Such satellite images can be displayed at the time of route
guidance. The satellite image server 300 transmits corresponding
satellite images to the navigation terminal in response to the request
for satellite images received from the navigation terminal.

[0030]The satellite image server 300 includes a number of image blocks. In
an exemplary implementation, all image blocks may have substantially the
same data size.

[0031]FIG. 3 illustrates a data structure of satellite images stored in
the satellite image server 300 according to an exemplary embodiment of
the present invention.

[0032]Referring to FIG. 3, image blocks 400 to 440 and image blocks 411 to
414 can be classified in consecutive resolution levels, according to the
height at which the ground is viewed. For example, the image block 400 of
resolution level 1 can cover the broadest area for each block, and the
image blocks 410, 420, 430 and 440 can cover a part (e.g. 1/4) of the
area of the image block 400 of resolution level 1. In an exemplary
implementation, one image block may have four image blocks that cover an
area of the image block. As a resolution level increases in such a
manner, each of the image blocks 400 and 410 has a number of child-image
blocks 410, 420, 430 and 440 and 411, 412, 413 and 414, respectively.

[0033]In an exemplary implementation, a zooming feature may be configured
for each of the image blocks so that controller 110 may zoom in or out
relative to a displayed image block according to a user input.

[0034]According to an exemplary embodiment of the present invention, the
satellite image requesting unit 114 requests the satellite image server
300 for image blocks corresponding to the locations on the route.

[0035]FIG. 4 illustrates image blocks corresponding to locations on a
navigation route according to an exemplary embodiment of the present
invention.

[0036]Referring to the left side of FIG. 4, a route from a starting point
indicated by a spot to a destination point indicated by reference
alphabet "G" is calculated. Referring to the right side of FIG. 4, the
satellite image requesting unit 114 requests the satellite image server
300 for image blocks 1 to 11 corresponding to locations on the route. In
this case, a process of downloading satellite images from the satellite
image server 300 is executed as a background process. More particularly,
while the satellite image requesting unit 114 downloads the satellite
images from the satellite image server 300, the controller 110 executes a
process of guiding a navigation route. The satellite image requesting
unit 114 stores the satellite images received from the satellite image
server 300 in the satellite image storage unit 116.

[0037]In the process of guiding a navigation route, the controller 110
acquires a current location. In this case, the current location may be
provided by a sensor (not shown), which may be a Global Positioning
System (GPS) or a Gyro/accelerometer (DR). Otherwise, the controller 110
can receive its own location information from a GPS satellite by means of
a GPS receiver (not shown). The controller 110 retrieves a satellite
image corresponding to the current location from the satellite image
storage unit 116 and then displays the retrieved satellite image on the
display unit 106. As shown in FIG. 4, the controller 110 can display both
the satellite image and a digital map for navigation on the display unit
106 by means of a split screen. Moreover, the controller 110 may overlap
and display both the satellite image and the digital map for navigation.

[0038]Hereinafter, an exemplary operation of guiding a navigation route by
a navigation terminal will be described with reference to FIG. 5.

[0039]FIG. 5 is a flow diagram showing a process of controlling navigation
route guidance by a navigation terminal according to an exemplary
embodiment of the present invention.

[0040]Referring to FIG. 5, in step 510, the controller 110 determines if a
destination is input by a user. As a result of the determination in step
510, when the destination is input by the user, the controller 110
proceeds to step 520 in which the controller 110 calculates a route from
a current location to the destination.

[0041]For example, referring to FIG. 4, when the user inputs a destination
indicated by "G," the controller 110 calculates a route using the route
calculation unit 112 and determines image blocks corresponding to the
route according to the calculated route information.

[0042]As described above, satellite images include a plurality of image
blocks mapped to corresponding locations on the route. Under the control
of the controller 110, the satellite image requesting unit 114 requests
the satellite image server 300 for the plurality of image blocks mapped
to the corresponding locations on the route. As an example, the satellite
image requesting unit 114 determines coordinates corresponding to the
locations on the route and then determines which image blocks to request.

[0044]At the same time, the controller 110 executes a process of
navigation route guidance in steps 530 to 580. First, in step 530, the
controller 110 calculates a current location of the navigation terminal.

[0045]In step 540, the controller 110 retrieves a satellite image
corresponding to the current location from the satellite image storage
unit 116. In step 550, the controller 110 displays the retrieved
satellite image on the display unit 106.

[0046]In step 580, the controller 110 determines if the navigation
function is completed. As a result of the determination in step 580, when
the navigation function is not completed, the controller 110 returns to
step 530 in which the controller 110 calculates a current location
changed according to the movement of the terminal.

[0047]According to exemplary embodiments of the present invention, a
terminal capable of receiving satellite images receives a satellite image
corresponding to a route during driving, and then performs navigation
guidance. That is, according to the present invention, a satellite image
server is previously requested for satellite images from a current
location to a destination, the satellite images are stored, and then the
stored satellite images are displayed to a user simultaneously with
navigation guidance. Therefore, according to exemplary embodiments of the
present invention, it is possible to effectively implement a navigation
function.

[0048]Certain aspects of the present invention can also be embodied as
computer readable code on a computer readable recording medium. A
computer readable recording medium is any data storage device that can
store data which can be thereafter read by a computer system. Examples of
the computer readable recording medium include read-only memory (ROM),
random-access memory (RAM), CD-ROMs, magnetic tapes, floppy disks,
optical data storage devices, and carrier waves (such as data
transmission through the Internet). The computer readable recording
medium can also be distributed over network coupled computer systems so
that the computer readable code is stored and executed in a distributed
fashion. Also, functional programs, code, and code segments for
accomplishing the present invention can be easily construed by
programmers skilled in the art to which the present invention pertains.

[0049]While the invention has been shown and described with reference to a
certain exemplary embodiments thereof, it will be understood by those
skilled in the art that various changes in form and details may be made
therein without departing from the spirit and scope of the invention as
defined by the appended claims and their equivalents.